Communications networks are susceptible to damage caused by a variety of natural and man-made disasters. Such damage typically occurs in either the digital cross-connect systems of the network or in the transport facilities that interconnect the digital cross-connect systems to each other. In either case, the damage causes communications failures at the trunk level, e.g., DS1, DS3, STS-N (SONET), or corresponding international rates, and all communication circuits passing over a failed trunk are disrupted.
Restoration of disrupted circuits by rerouting the communications they carry over spare circuits in the network is well known. Proposed prior art distributed systems for performing such rerouting employ a plurality of closely interconnected functions. These prior art systems are cumbersome in that they are neither easily upgraded nor are they easily reconfigured to control different types of digital cross-connect systems. Furthermore, they do not demonstrate sufficient robustness, i.e. speed of restoration and number of circuits restored, when there is massive damage to the network.